1. Field of the Invention
The invention relates to a waste gas treating device and a treating method using the same, and more particularly to a cross-flow biotrickling filter for treating waste gas and a treating method using the same.
2. Description of the Related Art
Biological waste gas purification technology is a major technology in the development of waste gas purification technology due to the advantages of mild operating conditions, low investment and operational costs as well as non-secondary pollution. A biotrickling filter is generally defined as a bioreactor, in which inert packing materials are partially or completely used to remove odorant pollutants in the air by means of manual inoculation of microorganism and continuous or intermittent spraying. Such a bioreactor has been considered to be a new generation of device for waste gas treatment owing to its advantages of wide applicable scope, high treatment load, and long service life.
The reactor construction of a biotrickling filter has an important influence on the reactor's applicable scope and performance; hence it is the first factor to be taken into account in its design. At present, most of the biotrickling filters under study and applications are solely of gas-liquid contact type, more specifically, it is either parallel-flow type or counter-flow type. A few of drum type and transverse-flow type biotrickling filters are used for laboratory research. However, in actual waste gas treatment site, pollutant gases contain complicated composition, especially in pharmaceutical factories, where the pollutant gases are composed of dozens of pollutants and the pollutants have completely different concentrations and physicochemical properties (e.g. water solubility, biodegradability and odour thresholds). As to the biotrickling filters of single gas-liquid contact type, it is difficult to achieve an ideal treatment effect on the waste gas, having multiple components, high concentration differences or having large differences as to physicochemical properties of those components.
Conventional biotrickling filters adopts a counter-flow structure or a drum structure to remove nitrogen oxides or odour produced, with a poor treatment effect.